1. Field of the Invention
The present invention relates to a signal processor. For example, it is concerned with an automatic control system in an apparatus such as a video camera, a digital still camera, etc.
2. Description of the Background Art
JP-A-6-14236 has described an object “to obtain safe and accurate focusing information from an image region (ranging frame) with exposure most suitable for AF and without high luminance” and use of a solution “a system control circuit changes an image region for detection of a focusing lens position when a high luminance detection circuit detects a high luminance portion”.
In the signal processor according to the background art, when there is a high luminance portion in a focusing lens position detection region currently selected, the region is changed. However, the change of the region is not performed after the absence of the high luminance portion in the changed region is confirmed, that is, a process of confirming the absence of the high luminance portion in the region is performed after the region is changed. Therefore, when there are a plurality of high luminance portions, there is a problem that it is necessary to repeat the change of the region and the process of confirming the absence of the high luminance portion.
In a method in which a plurality of focusing lens position detection regions are prepared so that an optimum one is extracted from the regions, there is a possibility that a high luminance portion may exist in any region in accordance with the size of each region, the size of each high luminance portion, the position of each high luminance portion and the number of high luminance portions. Therefore, there is a problem that there may be no optimum region.
However, the aforementioned problems have not been described in JP-A-6-14236.